Since we have not yet migrated to SAP HANA, we had to install three (3) new servers for our SAP ERP environment. Both the operating system (MS Server 2003) and the SQL version (MS 2005) of our “old” servers were not suitable to migrate to SAP HANA or even – temporarily – to EHP 6. And the server hardware has also aged a bit, so we decided to do a complete changeover. We have also undergone a change from dedicated servers to virtual servers. If you already use state-of-the-art hardware with a modern operating system and DB, this step is not mandatory when migrating to HANA DB.

As always – interfaces require special attention!

We have organized the hardware replacement in such a way that we were able to maintain the previous IP addresses and had to change host names only. This lowers the requirements to adapt the interfaces quite a bit.

However, the reactivation of our interfaces took a few days to complete. We were especially grateful for the fact that our list of interfaces has recently been brought up to date. So we knew right off where we had to lend a hand – namely, at about 40 internal and external interfaces. After the reactivation phase we did the testing phase. We were amazed that, for example, the tax office to which we submit the monthly salaries of our colleagues does not require mandatory testing to be done. Nothing we could do about that and therefore the next transfer to the tax office was the real test – and it all worked out. In hindsight, we can say that all interfaces had passed the test.

Question: Testing with key users or by IT?

Good question and we did think about it. If testing is performed with key users, their experience and knowledge in their respective businesses areas is a good argument to do so. On the other hand the testing phase will also become more time-consuming, since ultimately much more users must be integrated and coordinated. We finally decided to have the testing done by IT, because within the SAP IT team we have an in-depth understanding of our business processes. In addition, if testing is done with key users, almost all of the 18 countries must be integrated. We did not want to go so far. In the end, we think we did the right thing with our decision. However, it is best to consider from case to case what is possible with the team at hand.

All in all we have needed 4 weeks for the testing phase and we are glad to say that we did not have to overcome major obstacles. Our ERP environment – consisting of development system, test system, and production system – is now running on the new servers. Currently, we are already in WAVE 2. More about that next week. Until then.

Want to know more about WAVE 0? Read part one of my blog series here and part two here.